They are halogen elements, or nonmetallic elements in the same GROUP, specifically group 17
Blue light can knock electrons off a plate, but red light can't
Answer:
3g/cm³
Explanation:
<em>Use the formula:</em>
density = mass ÷ volume
<em>Substitute (plug in) the values:</em>
density = 3 ÷ 1 = 3g/cm³
Answer: The square root of Pi is 1.77245.
Please mark as brainliest