An electromagnet can be made by wrapping wire around witch object?

The following image is of a diatom. it lives in water and gets food from photosynthesis. it is encased in a hard shell made of something similar to glass or sand . a diatom is a(n) because it has a) multi-celled organism; specialized parts. b) vertebrate; a skeleton. c) insect; an exoskeleton. d) single-called organism; only one cell.

Indica el nombre y la fucion de los vasos sanguineos que entran y salen de los riñones

Spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?