Three blocks - physics diagram

I did the work but need your suggestion. (see attachment)

Maximizing a function

what value of x will maximize: r(x)=r^2*(ln(1/x)? x can take values between 1/4 and 1

Lowest standard deviation of measurements

See below: As the Quality Control Manager of a chemical company, you are asked to decide between several process methods that are supposed to uniformly mix 37.4 milligrams into a chemical solution. The resulting solutions from each process are sample tested for uniformity. The test samples yielded the following results of percentage powder mixed in the solution: Method A: 0.13%, 0.21%, 0.009%, 0.014% Method B: 0.10%, 0.006%, 0.015%, 0.11%, 0.16% Method C: 0.006%, 0.09%, 0.07% Method D: 0.18%, 0.16%, 0.19%, 0.17% Which method would be the best choice to provide a uniform mixture??? (Hint: The best selection would be that resulting in the lowest standard deviation of measurements ... click for more

workout velocity and range of shell fired

1. Why is it possible to consider the vertical and horizontal motion of a projectile independently of each other. 2. A mortar shell fired with an angle of elevation of 50degrees ahs a range of 2.5km. Neglecting air resistance determine: a. The time of flight. b. The shells initial velocity. c. The shells range and height 30s after firing. d. The other range at which the height was the same as calculated in part c above.

Consider the scalar field (pressure field)

Consider the scalar field (pressure field) given by the function f(x,y)=9x2 + 4y2 Q: Find the isobars (curves of constant pressure) and sketch some of them. Complete problem in attached file...