Please answer all the step wise step factorise
1. a^2 - b^2 - 4a +4

2. x^2 -xy - 3x +2 +2y

3. 4x^2 - 4a^2 - 4a - 1

4. x^2 + 3x + 2 + ax + 2a

5. 7 ( x - 1/x )^2 + 15 ( x - 1/x ) + 2

6. 64 - 144x + 108x^2 - 27x^3

7. ab^2 - b ( a-c ) - c

8. p^2 - a ^2 - 2pr + r^2

Which equation can be solved to find x the measure of jk in the apex

The weekly amount spent by a company for travel has an approximately normal distribution with mean = $550 and standard deviation = $40. a) what is the probability that the actual weekly expense will exceed $570 for more than 20 weeks during the next year? (note: one year = 52 weeks) b) what is the probability that actual weekly expenses exceed $580 for 10 or more, but 16 or fewer weeks during the next year?

∠a and ∠ b are complementary. if m∠ b = 80°, what is the measure of ∠ a? 10° 80° 90° 100°