1. PbO is a possible formula units, since O has charge of 2- and Pb can have a charge of 2+ or 4+, if it uses the 2+ ion, the charges will balance out to form PbO. Li+ and B(3-) would have Li3B, Al(3+) and Pb(2+) are both positive charges and would not balance out, Cl- and O(2-) are both negative charges and would not balance out.
2. Iodine is a halogen, so it has a charge of -1. Calcium is an alkaline earth metal in Group 2, so it has a charge of 2+. Therefore, if they were to form a formula unit, the resultant would be CaI2 (2 iodine atoms of 1- charge are needed to balance out the 2+ charge on the calcium atom).
3. Strontium is an alkaline earth metal with a charge of 2+, while phosphorus has a charge of 3-. Therefore, to balance the charges out, we would need 3 atoms of strontium and 2 atoms of phosphorus. This would give the formula unit of Sr3P2.
Independent of the conditions of the outside of the cell
The birds, because we can see from the food web that the bird eats both grain, a producer, and grasshoppers, a consumer.
True, because computers are digital machines, as they can read information.
