The first one? If not I just guessed
Answer:
v = 1.32 10² m
Explanation:
In this case we are going to use the universal gravitation equation and Newton's second law
F = G m M / r²
F = m a
In this case the acceleration is centripetal
a = v² / r
The force is given by the gravitational force
G m M / r² = m v² / r
G M/r = v²
Let's calculate the mass of the planet
M = v² r / G
M = (1.75 10⁴)² 5.00 10⁶ / 6.67 10⁻¹¹
M = 2.30 10²¹ kg
With this die we clear the equation to find the orbit of the second satellite
v = √ G M / r
v = √ (6.67 10⁻¹¹ 2.30 10²¹ / 8.75 10⁶)
v = 1.32 10² m
You would know a decomposition reaction occurred if the reactants separated. For example from AB → A+B.
Now if you look at your options only 1 works out for that equation. Letter A.
From the compound K2CO3 it split up to K2O +CO2
It cannot be letter B because synthesis/combination occurred. The same goes for letter C. Letter D, single displacement occurred.
Again, the answer is A.
Answer: P= mad/t or P=w/t so P= 300/6= 50 W