Question : Two taps A and B can fill a tank in 10 hours and 12 hours respectively. If the two taps are opened at 10 AM, at what time (in PM) should tap A be closed to fill the tank at exactly 4 PM?

Option 1: 2:00

Option 2: 3:00

Option 3: 1:00

Option 4: 1:30

Question : The length of the shadow of a vertical pole on the ground is 36 m. If the angle of elevation of the sun at that time is $\theta$. Such that $\sec \theta=\frac{13}{12}$, then what is the height (in m) of the pole?

Option 1: 12

Option 2: 15

Option 3: 18

Option 4: 9

Question : The length of the shadow of a vertical pole on the ground is 18 m. If the angle of elevation of the sun at that time is $\theta$, such that $\cos \theta=\frac{12}{13}$, then what is the height (in m) of the pole?

Option 1: 7.5

Option 2: 9

Option 3: 18

Option 4: 12

Question : An equinox is when:

Option 1: day and night are of equal length

Option 2: day is the shortest duration in the year

Option 3: day is the longest duration in the year

Option 4: day when maximum rainfall of the year occurs

Question : A trader buys an article at 80% of its marked price and sells it at a 10% discount on its marked price. His percentage profit is:

Option 1: $10 \frac{1}{2}$

Option 2: $10$

Option 3: $12 \frac{1}{2}$

Option 4: $15$