<h3><u>Answer;</u></h3>
- In a freshwater lake
- In the atmosphere
- In Earth's mantle
<h3><u>Explanation</u>;</h3>
- <em><u>Convection currents are types that cause the process of convection, which the transfer of heat energy that occurs in fluids.</u></em>
- <em><u>Convection currents are circular patterns that occurs in fluids such that the less dense warm fluids rises up while denser cold fluids sinks, </u></em>it is this movement of less dense warm fluid and denser cold fluids that creates circular patterns that causes the process of convection to take place.
- <em><u>Convection currents may occur in the atmosphere where warm air rises while cold denser air sinks or moves towards the bottom, it may also occur in the mantle of the Earth and water or water bodies such as lakes.</u></em>
From the information given above,
Mass [M] = 28 g
Change in temperature = 29 - 7 = 22
Specific heat of iron = 0.449 [This value is constant]
The formula for calculating heat absorbed, Q is
Q = Mass * Specific heat of Iron * change in temperature
Q = 28 * 0.449 * 22 = 276.58 J<span />
Answer:
The resistance that will provide this potential drop is 388.89 ohms.
Explanation:
Given;
Voltage source, E = 12 V
Voltage rating of the lamp, V = 5 V
Current through the lamp, I = 18 mA
Extra voltage or potential drop, IR = E- V
IR = 12 V - 5 V = 7 V
The resistance that will provide this potential drop (7 V) is calculated as follows:
IR = V

Therefore, the resistance that will provide this potential drop is 388.89 ohms.
heat from water goes into air in ball
air expands
ping goes the dent