If I did my math right I believe 13 is the 9.3 seconds and 14 is the first option because of logic. The question basically says, how does the height change and the answer is the first one because it gets higher then lower, or increases then decreases.
C because...
Models represent objects, events, and processes in the real world.
Models are often used when an object, event, or process
occurs too slowly or too quickly;
is too small or too large;
is too complicated or too dangerous.
The ocean is spreading at such a slow rate that it would take scientists 50 or more years to collect enough meaningful data from the ocean floor to complete a study. Therefore, scientists use models in order to both predict how the floor will keep spreading and to understand what the ocean floor looked like thousands of years in the past.
The frequency of bird chirping hear by hiran will be 1.77 kHz.
<u>Explanation:</u>
As per Doppler effect, the observer will feel a decrease in the frequency of the receiving signal if the source is moving away from the observer. So the shifted frequency is obtained using the below equation:

Here , c is the speed of sound, Vs is the velocity of source with which it is moving away. f is the original frequency of source and f' is the frequency shift heard by the observer.
As here, f = 1800 Hz, Vs= 6 m/s and c = 343 m/s, then

So, the frequency of bird chirping hear by hiran will be 1.77 kHz.
False<span>, well designed weight training programs actually target most of the muscles in the body. A good weight training program includes many compound exercises to activate multiple muscle groups and promote muscle hypertrophy. Some isolation exercises may also be included to target a specific muscle and help it grow.</span>