Need help with algebra Please!!

1. Simplify. 5–1(3–2) (1 point)
   

A)45

B)1/45

C)15^–3

D)15^2 ----------------

1. Simplify. mn^-4/p^0q^-2 (1 point)
   

A)mq^2/n^4

B)mp/n^4

C)mn^4q^2p^0

D)q^2/mn^4 ----------------

1. Write in scientific notation. 0.0042 (1 point)
   

A)42 × 10^2

B)4.2 × 10^4

C)4.2 × 10^3 ----------------

D).42 × 10^4

1. Write in standard notation. 6.12 × 10^3 (1 point)
   

A)6,120 ----------------

B)612

C)61,200

D)61.2

1. Simplify. Write in scientific notation. 0.5(8 × 10^5) (1 point)
   

A)8 × 5^5

B)4 × 5^5

C)8 × 10^5

D)4 × 10^5 ----------------

1. Simplify. Write in scientific notation. (9 × 10^3)^2 (1 point)
   

A)8.1 × 10^5

B)81 × 10^4

C)81 × 10^3

D)8.1 × 10^6 ----------------

1. Evaluate 1/2a^4b^2 for a = –2 and b = 4. (1 point)
   

A)2 ----------------

B)1/2

C)3

D)4

1. Is the following statement always, never, or sometimes true?
   

A number raised to a negative exponent is negative. (1 point)

A)always

B)never

C)sometimes ----------------

1. Simplify (4xy^2)^3(xy)^5 (1 point)
   

A)64x^8y^11

B)64x^15y^30

C)12x^2y^11

D)12x^8y^11 ----------------

1. Simplify (2t^3)^3(0.4r)^2 (1 point)
   

A)3.2r^2

B)1.28r^2/t^-6 ----------------

C)1.28r^2/t^9

D)0.8r^2/t^-6