She started with x.
After 1 year, she had 1.025x.
She withdrew <span>£1000, so now she has 1.025x - 1000.
Then it earned interest for 1 year and ended up as </span>1.025(1.025x - 1000).
The actual amount of money was £23 517.60.
Therefore,
<span>1.025(1.025x - 1000) = 23517.60
1.025x - 1000 = 22 944
1.025x = 23 944
x = 23 360
Her original deposit was </span><span>£23 360</span>
Looking at the graph closely we can see that the heart rate increases from 0 to 6 min then became steady from 6 to 25 min then finally decreases from 25 to 30 min. Therefore the correct answer is:
“The heart rate increases for 6 minutes, remains constant for 19 minutes, and then gradually decreases for 5 minutes.”
In real life cardiac exercises, we can interpret that the period from 0 to 6 min is the period where the person is still warming up thus leading to an increase in heart rate. At 6 min, the person is fully warmed up hence reaching a stable heart rate. Then at 25 min, the person starts cooling down which means that the exercise is ending soon.
I completely forgot how to do this but maybe multiply the angles I’m so sorry