Answer:
40 s
Explanation:
After 10 seconds, the first skater would have a 8m/s * 10s = 80 m head start
Let t be the number of seconds after the second skater starts will the second skater overtake the first skater
The distance traveled by the first skater after t seconds is

Similarly the distance traveled by the 2nd skater after t seconds is

Since the 2nd skater catches up to the 1st one after 80 m behind, the distance traveled by the 2nd one must be 80m greater than the distance of the 1st skater

We can substitute 



Density is mass divided by volume. rho=m/v. So, v=m/rho. In frank's case this is 80/8 = 10 cm^3.
Answer:
21
Explanation: its actually 20.85 but i guess they round to 21
<span>Rayed craters-</span><span> were the last features to form on the moon.</span>
Answer:
Moment of inertia of the solid sphere:
I
s
=
2
5
M
R
2
.
.
.
.
.
.
.
.
.
.
.
(
1
)
Is=25MR2...........(1)
Here, the mass of the sphere is
M
M