Answer:
D. 7 +11i
Step-by-step explanation:
In many situations, you can treat "i" as though it were a variable. Collect terms in the usual way.
(2 +8i) -(-5-3i) = 2 +8i +5 +3i = (2+5) +(8+3)i
= 7 +11i
Events
• A: an even number is rolled in the first time
,
• B: a number greater than 3 is rolled the second time
The probability of rolling an even number is:

The probability of rolling a number greater than 3 is:

Events A and B are independent, then the probability of one happening after the other is:
The angle of depression is 29.0521°. So it is a safe landing.
Step-by-step explanation:
Step 1:
The plane is flying at a height of 25,000 feet and 45,000 feet away from the landing strip. Assume it lands with an angle of depression of x°.
So a right-angled triangle can be formed using these measurements. The triangle's opposite side measures 25,000 feet while the adjacent side measures 45,000 feet. The angle of the triangle is x°.
To determine the value of x, we calculate the tan of the given triangle.

Step 2:
The length of the opposite side = 25,000 feet.
The length of the adjacent side = 45,000 feet.

So x = 29.0521°. Since x < 30°, it is a safe landing.
<span>A.
The surface area of A is greater than the surface area of B.</span>