a boy sitting on a platform 7.5m high he observes that the angle of elevation of the top of the opposite building is 40°.the platform is 37.5m away from the building .find the height of the building

The building is approximately 39 m high.

Step-by-step explanation:

As seen in the diagram attached, a triangle can be formed between the boy, the top of the building, and the lateral distance between the boy and the building.

We can now use trigonometric laws to find the distance AC between the boy's head and the top of the building.

tan 40 = AC/37.5

AC = 37.5 X tan 40 = 31.46m

We have just obtained the distance from the boy's head to the building top.

To get the true height of the building, we have to add the height of the platform the boy is standing on to the value just found.

7.5m + 31.46m = 39m

if gloria has "carry over" minutes, (that is, any minutes paid for but not used in a month can be applied to her payment for minutes in the next month,) her total usage for the three months is: total minutes = 320 + 243 + 489 = 1052 minutes number of 200 minute blocks = 1052/200 = 5 r52 (that is 5 with a remainder of 52) rounding up the number of 200 minute blocks gives her usage for the three months as 6 blocks. the cost for six blocks is 6 x $25 = $150 she also has 200 - 52 or 148 carry over minutes if gloria pays each month and unused minutes are lost, applying the rounding up procedure to each month gives: first month usage of 320 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 second month usage of 243 minutes rounds up to 2 blocks of 200 minutes for a payment of 2 x $25 = $50 third month usage of 489 minutes rounds up to 3 blocks of 200 minutes for a payment of 3 x $25 = $75 total payments for the three months are $50 + $50 + $75 = $175 get the plan with carry over minutes!