Answer:
A, B and D are true statements.
Step-by-step explanation:
We are given a binomial expansion


Now we will check each option
Option A: The coefficients of
and
both equal 1.
If we see first and last term of the expansion, This statement is true.
Option B: For any term
in the expansion, a + b = n.
Let we take 3rd term of expansion
Here, a=n-2 and b=2
If we do a+b = n-2+2=n
a+b=n is true statement.
Option C: For any term x^ay^b in the expansion, a - b = n.
Let we take 3rd term of expansion
Here, a=n-2 and b=2
If we do a-b = n-2-2=n-4≠n
a-b=n is false statement.
Option D: The coefficients of x^ay^b and x^by^a are equal.
If we take second term from beginning and last of the expansion.


This statement true.
Let the angle be x.
Hence, its complement is 90 - x.
x = 3* (90 - x) - 70 = 270 - 3x - 70 = 200 - 3x
4x = 200
x = 50
Thus, the angle is 50°.
Answer:
240
Step-by-step explanation:
240 + 60 = 300 you can tell this by realising that ratio to have 4x one over the other would be 20 per 100, using this rate 3x, 240 and 60
Sorry I can’t buddy........................................................:(