The right answer would be
-20t+ 80
You would want it to be greater than D. friction force
It needs be greater than the friction applied to it.
Because other scientists and science in general rely on their collegues' research which in turn allows development of our knowledge on the given subject. The more dont-to-earth reason may be safety. If someone performs an experiment without knowledge of its true results it might result in some danger to the safety of those perforning it without knowledge of all the risks.
Answer:
The sea level will be 5m higher in 1667 y (years)
Explanation:
From the question, the rate at which the ocean's level is currently rising is about 3mm per year.
First, we will convert mm (millimeter) to m (meter)
1 mm = 0.001 m
Then,
3 mm = 3 × 0.001 m
= 0.003m
That is, the rate at which the ocean's level is currently rising is about 0.003m per year.
Now, to determine how long it will take for the ocean's level be 5 m higher than now at the given rate,
If the ocean rises 0.003 m in 1 year, then
the ocean will rise 5 m in x years
x = (5 m × 1 year) / 0.003 m
x = 5 / 0.003
x = 1666.67 years
x ≅ 1667 years
Hence, the sea level will be 5m higher in 1667 y (years)