**Answer: **Scientific Notation is the expression of a number n in the form a∗10b. where a is an integer such that 1≤|a|<10. and b is an integer too. Multiplication: To multiply numbers in scientific notation, multiply the decimal numbers. Then add the exponents of the powers of 10.

**Step-by-step explanation:**

D and E

the triangle is right as it has a right angle as one of the 3 angles

the triangle is isosceles as it has 2 equal sides , indicated by the score on the equal sides and 2 equal base angles of 45°

= -3/2 * -5 1/4

convert 5 1/4 to improper fraction

= -3/2 * -21/4

multiply numerators; multiply denominators

= (-3*-21)/(2*4)

multiply in parentheses

= 63/8

convert back to mixed number

= 7 7/8

ANSWER: Since the exact answer is the mixed number 7 7/8, a reasonable estimate is 8.

Hope this helps! :)

**Answer:**

**Percentage change in price = 13.80%**

**Step-by-step explanation:**

Given that:

Original price = £57.99

Decreased price = £49.99

Difference = Original price - Decreased price

Difference = 57.99 - 49.99

Difference = £8.00

Percent change =

Percent change =

Percent change in price = 13.80%

Hence,

**Percentage change = 13.80%**