Incomplete question as the car's speed is missing.I have assumed car's speed as 6.0m/s.The complete question is here
An amusement park ride consists of a car moving in a vertical circle on the end of a rigid boom of negligible mass. The combined weight of the car and riders is 6.00 kN, and the radius of the circle is 15.0 m. At the top of the circle, (a) what is the force FB on the car from the boom (using the minus sign for downward direction) if the car's speed is v 6.0m/s
Answer:

Explanation:
Set up force equation
∑F=ma
∑F=W+FB
The minus sign for downward direction
Answer:
is there any choice? in this question?
Two dangerous elements can form a compound that is edible known as "NaCl salt".
<u>Explanation:</u>
Sodium and chlorine are two very dangerous elements. As the reaction between sodium and water is extremely violent and chlorine is a very toxic gas. But combination of these elements result into a harmless product with unique properties like it is edible and dissolves without exploding in water.
In sodium chloride reaction the atoms of sodium interact with chlorine atoms. Sodium will donate an electron (by becoming positively charged) to acceptor chlorine (which become negatively charged) as given in following reaction

As sodium and chlorine are very keen to achieve noble gas configuration by completing an octet on donating and accepting an electron respectively.
Answer:
(C) They consist of ice.
Explanation:
Comet consist of a body of ice, rock and dust that can be several miles in diameter and orbits the sun. Debris from comets is the main source of many meteoroids.
Answer:
mas of water displaced = 41.4 g
Explanation:
Weight in air = True weight = 45 g
Apparent weight = 3.6 g
Apparent weight = True weight - Buoyant force
Buoyant force = 45 g - 3.6 g = 41.4 g
Weight of water displaced = Buoyant force
Weight of water displaced = 41.4 g dyne
mas of water displaced = 41.4 g