Which of these measurements is expressed as three significant figures?
C. 4.20 g
The answer is (2). If you recall Rutherford's gold foil experiment, remember that a stream of positively charged alpha particles were shot at a gold foil in the center of a detector ring. The important observation was that although most of the particles passed straight through the foil without being deflected, a tiny fraction of the alpha particles were deflected off the axis of the shot, and some were even deflected almost back to the point from which they were shot. The fact that some of the alpha particles were deflected indicated a positive charge (because same charges repel), and the fact that only a small fraction of the particles were deflected indicated that the positive charge was concentrated in a small area, probably residing at the center of the atom.
Answer:
d = 0.93 g/cm³
Explanation:
Given data:
Mass of object = 28 g
Volume of object = 3cm×2cm×5cm
density of object = ?
Solution:
Volume of object = 3cm × 2cm ×5cm
Volume of object = 30 cm³
Density of object:
d = m/v
by putting values,
d = 28 g/ 30 cm³
d = 0.93 g/cm³
Answer:
Single-celled organisms use cell division as their method of reproduction. Cell Division and Growth: A sea urchin begins life as a single cell that (a) divides to form two cells, visible by scanning electron microscopy.
Explanation:
Los organismos unicelulares utilizan la división celular como método de reproducción. División y crecimiento celular: un erizo de mar comienza su vida como una sola célula que (a) se divide para formar dos células, visibles mediante microscopía electrónica de barrido.
