A.<span>640/(120+w)
...............................................................................................................................................................................</span>
First set up the equation:

+

Now solve the ones in the parenthesis:

+

Then do the exponents:
25+64
The answer will be:<u> </u>
<u>89
</u>Hope this helps!
<u>
</u>
The mass of the rock in kg is 90,000 kg
Answer:
0.125 inches per hour
Step-by-step explanation:
2.25/18 = 0.125
0.125in per hour