If E(X) = 5, V(X) = 3 and Y = 5 - X/3 - X, what is mean of Y?

A battery can provide a current of 3.4 A at 2.2 V for 1.5 hr. How much energy (in kj) is produced?

What is the % concentration (m/v) of a solution prepared by dissolving 10.0g of NaOH in enough water to make 225mL of solution?

A communication satellite is in circular orbit of a radius 2 DU.find minimum delta-v required to double the altitude of satellite.

A magnetic field with induction B = 15 · 10−4T is directed perpendicular to the electric field with intensity E = 10V /cm. The beam of electrons flying at the speed v enters the space with the mentioned fields. The velocity of the electrons is perpendicular to the plane containing the vectors E and B. Calculate: 1) the electron velocity v, if the electron beam does not deviate under the simultaneous action of both fields; 2) the radius of curvature of the electron trajectory when only the magnetic field is on. 3) What is the kinetic energy of the electron in both cases?

Given that a sample is approximately normal with a mean of 25 and a standard deviation of 2, the approximate percentage of observation that falls between 19 and 31 is:

                     i.   67%

                     ii. 75%

                     iii. 95%

                     iv. 99.7%

                     v. can’t be determined with the information given

e.    The Law of Large Numbers implies the following:

               i. To calculate a probability an experiment needs to be theoretically                                                              

                           repeated

                     ii.   Probabilities can be calculated on sampling distributions

                     iii. The Law does not apply to subjective probabilities

                     iv. All of the above

                     v.   None of the above

3) Solve the initial value problems

c) R′ + (R/t) = (2/(1+t² )) , R(1) = ln 8.

e) ) cos θv′ + v = 3 , v(π/2) = 1.

5) Express the general solution of the equation x ′ = 2tx + 1 in terms of the erf function.

7) Solve x ′′ + x ′ = 3t by substituting y = x ′

9) Find the general solution to the differential equation x ′ = ax + b, where a and b are constants, first by separation of variables, and second by integrating factors

A three phase 30 hp 460 volt 60 hz, 1770 rpm design B induction motor with class F insulation and service factor of 1.0 is operating at rated shaft load in a 40 degree C environment and has an expected 20 yr life. A maintenance check shows line to line voltages to be 449.2 V, 431.3 V and 462.4 volts. The percent unbalanced voltage for this motor is:

the expected temperature rise equals?

The expected insulation life equals?

the rerating in horsepower equals?

Anna dissolves 32. grams of glucose with water and the final volume of solute and solvent is 122. mL. What is the concentration of glucose in her solution using the %(m/v) method? Amanda dissolves 0.14 moles of NaCl in 300 ml of solution. What is the concentration of NaCl in the solution using the molarity method? Remember that 1,000 mL = 1 Liter

Anna dissolves 32. grams of glucose with water and the final volume of solute and solvent is 122. mL. What is the concentration of glucose in her solution using the %(m/v) method