18. A radioactive element has a half-life of 18,000 years. There was 400 grams of the element originally. There is now 12.5 grams of the radioactive element left. What is the age of the
sample?

Pls! plant cells and animal cells were observed under a microscope. the characteristics of two cells are listed below. cell p: does not capture sunlight cell q: has cytoplasm but no chloroplast which statement about the two cells is correct? cell q also has a cell wall. cell q also has large vacuole. cell p also has a large vacuole. cell p also has a cell membrane.

Which compound contains both ionic and covalent bonds? a) hbr b)cbr4 c)nabr d) naoh

Δu of , in kj/kg, as it isto k, (a)as a of , (b) at , (c) at .