Answer:
A. Danny stores the chemicals required for his experiment in flasks and beakers.
Explanation:
It is unsafe to store chemicals in open containers such as, a flask or beaker.
Answer:
b. passive solar heating
Explanation:
Passive solar heating is a system designed to use solar energy (energy from the sun) for the purpose of providing electricity or heat. This system is used in households and offices to absorb, retain and supply heat to the desired location.
This system is termed "passive" because it does not require any external device for conversion of solar energy rather it exploits sun's energy directly. Hence, according to this question, PASSIVE SOLAR HEATING is the form of renewable energy that uses the sun's energy most directly.
It stays the same. There arent factors that are changing the environment like humans cutting down trees.
