Answer:
Hydraulic press is called an instrument for multiplication of force. Why? Because it uses Pascal's idea and principle: F=p*S. If we apply small force to small piston you will generate a pressure. According to Pascal's law pressure is the same everywhere in closed system so the same pressure will act on large piston on the other side too.
Explanation:
Area of a circle is
A= pi r^2
so
500m^2 = 3.14 r2
500/pi = r ^2
152.1549...=r^2
square root both sides
r=12.61566...
d=2r
d=25.2
to 3 sig fig
Answer:

Explanation:
Speed of light is the product of its wavelength and frequency, expressed as
S=fw
Where s represent speed, f is frequency while w is wavelength
Making f the subject of the formula then
f=s/w
Substituting 2.99x10^8 m/s for s and 3.012x10^-12 m for w then

Therefore, the frequency equals to 
Answer:
D. Checking to see if the brake fluid is contaminated
Explanation: