A factory makes toys. The probability that a toy is defective is 0.03. A random sample of 50 toys is tested. (a) Find the expected number of defective toys. [2] {b} Find the probe bility that there is at least one defective toy in the sample. [3] {e} Given that there is at least one detective toy in the sample, nd the [3] probability that there are, at most, three defective - l. lint-r3: "