A=3 square root of 3
B=3
C=7
D=6

Step-by-step explanation:

This triangle is a 30°-60°-90° triangle, so you should always remember the rule shown in the picture. Because y is across from the 60° angle, it will be . 3 is x because it is across from the 30° angle, so y will be .

reduce the friction between its moving parts

step-by-step explanation:

in fact, by reducing the friction between the moving parts of the machine, it is possible to reduce the energy wasted due to this friction; therefore, more input energy is converted into useful work, and this will improve the efficiency of the machine.