They become old and explode.
The pressure exerted by the block on the table is given by:
where W is the weight of the box, and A is the bottom surface area of the box.
The weight of the box is: 
Substituting into the first equation, we find the pressure:
Answer: Symbol A
Explanation:
The four symbols described here represent:
- Symbol A shows two dots and a line draw from one not connected to the other. --> this is an open switch. A switch is component of a circuit that is used to open/close the circuit in order to interrupt/allow the flow of current through the circuit. In this case, the switch is open, since the line does not connect the second dot.
- Symbol B shows two dots and a line draw from one connected to the other. --> this is the symbol used to represent the switch when it is closed, so it is a closed switch.
- Symbol C shows vertical lines in the pattern long, short, long, and short with a plus and minus symbol on it. --> this symbol represents a battery, which consists of two or more cells and provides the electromotive force that pushes the electrons along the circuit.
Therefore, the correct symbol representing the open switch is
Symbol A
Answer: 3- Large cells of rising and sinking gasses
Explanation: Hotter gas coming from the radiative zone expands and rises through the convective zone. It can do this because the convective zone is cooler than the radiative zone and therefore less dense. As the gas rises, it cools and begins to sink again. As it falls down to the top of the radiative zone, it heats up and starts to rise. This process repeats, creating convection currents and the visual effect of boiling on the Sun's surface.
Answer:
47.5kJ
Explanation:
Before climbing the cliff
At 2.
