Answer:
1.D
2.C
3.D
4.D
5.C
6 B
those are the answers, we must take care of our environment
Answer:
1.The metalloids; boron (B), silicon (Si), germanium (Ge), arsenic (As), antimony (Sb), tellurium (Te), polonium (Po) and astatine (At) are the elements found along the step like line between metals and non-metals of the periodic table.
2.hydrogen
The elements generally classified as nonmetals include one element in group 1 (hydrogen);
3.element iron
The element iron is in group 8, and therefore has two or three apparent valence electrons.
Density is the mass of compound divided by its volume can be shown as follows:


40 mL of snow having 20 g of mass calculated from density.
Now, 10 cm of snow = 3.93 inches = 20 g
As, 10 inches of rain will produce 11 inches of ice as the volume of ice is bigger than rain water.
10 inches rain = 11 inches snow
3.93 inches of snow produced by

Thus, 3.57 incehs of rain produces by 10 cm snow.
Answer: Precision means that measurements are close to each other . Accuracy means that measurements are close to accepted value
Explanation:
Precision refers to the closeness of two or more measurements to each other.
For Example: If we weigh a given substance five times and you get 5.0 kg each time. Then the measurement is very precise.
Accuracy refers to the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 5.0 kg and one person weighed 4.9 kg and another person weighed 3.9 kg. Then, the weight measured by first person is more accurate.
Thus Precision means that measurements are close to each other . Accuracy means that measurements are close to accepted value.