OMG PLS HELP WITH THIS IM PANICKING OMG I GOT A F IN MATH MY MOM JUST YELLED AT ME IM CRYING PLS HELP WITH THS-

Sorry about that, here's the answers.
1. expanded form
2. regroup
3. place value
4. A, C, D. The strategy I used was place value and regrouping. I chose these by using place value to help me understand how to regroup and what each option would sum to.
5. D. Ten thousands place
Answer:
1. Expanded form
2. Regroup
3. Place value
4. A, C, D,
C is correct because a one is equal to 1.
1 x 4,200 = 4,200. Therefore 4,200 ones is equal to 4,200. D is correct because a ten is equal to 10. 10 x 420 = 4,200. Therefore, 420 tens is equal to 4,200. A is the same as the rest but with hundreds.
5. A
Step-by-step explanation:
1. Expanded form refers to when a number is separated by place values. Like 555,555 being turned into 500,000 + 50,000 + 5,000 + 500 + 50 + 5.
2. Regrouping is separating number by places values to do an equation like subtraction. For example, 5 tens - two ones.
3. Place values refers to a digit in a number like the 1 in 2,134 is in the hundreds place and the 5 in 5,677 is the thousands place.
4. My answer explains it.
5. A is correct as the 2 in 321,705 is 20,000 while the 2 in 32,571 is 2,000. 20,000 is 10 times larger than 2,000. So the answer is 10.