A tree is 3,212 years old. How can you express this age in scientific notation with the lowest level of precision? 3 x 10^3
3.2 x 10^3
3.21 x 10^3
3.212 x 10^3

I'm not certain, but I believe it is A. Could some check please? Asap! Tysm!

Solve each quadratic equation by factoring and using the zero product property. x^2 - 8x + 30 = 3x

Given: lines a and b are parallel and line c is a transversal. prove: 2 is supplementary to 8 what is the missing reason in the proof? statement reason 1. a || b, is a transv 1. given 2. ∠6 ≅ ∠2 2. ? 3. m∠6 = m∠2 3. def. of congruent 4. ∠6 is supp. to ∠8 4. def. of linear pair 5. ∠2 is supp. to ∠8 5. congruent supplements theorem corresponding angles theorem alternate interior angles theorem vertical angles theorem alternate exterior angles theorem

Which problem would you use the following proportion to solve for? 24/x=40/100 a. what is 40% of 24? b. what percent is 24 of 40? c. twenty-four is 40% of what number? d. forty percent of 24 is what number?