False; the three major scales used to measure earthquakes are the Mercalli Scale, the Richter Scale, and the Magnitude Scale. I hope this helps!
If it's Kepler's law of equal areas you're talking about,
then the first of the four statements is true.
A screw driver rusting when left in a pail of water is a chemical reaction
To what i see, the answer is....
C.
Using Newton's law that F = ma.
The force here is the net force. The forces acting in opposite direction are the weight and the air resistance. The weight of course is acting downwards and the air resistance is pushing upwards.
Therefore:
W - AR = ma W = Weight = mg, AR = Air Resistance = 150.
g = 10 m/s2
mg - AR = ma
60(10) - 150 = 60a
600 - 150 = 60a
450 = 60a
60a = 450
a = 450/60
a = 7.5 m/s2
Cheers.