In Cipher Block Chaining (CBC) mode, decryption is obviously the symmetric counterpart to encryption, because the inverse operations are used in the reverse order; but in Counter (CTR) mode, decryption is the same as encryption except that the plaintext and ciphertext blocks are swapped. Briefly explain why Counter mode is symmetric, despite this apparent contradiction.

The width of a piece of rectangular land is 5m shorter rhan 1/3 of its length .find the width of the land if the length is 60m,150m.

Assume that minutes is an int variable whose value is 0 or positive. write an expression whose value is "undercooked" or "soft-boiled" or "medium-boiled" or "hard-boiled" or "overcooked" based on the value of minutes. in particular: if the value of minutes is less than 2 the expression's value is "undercooked"; 2-4 would be a "soft-boiled", 5-7 would be "medium-boiled", 8-11 would be "hard-boiled" and 12 or more would be a "overcooked".

How do we use the sumif formula (when dealing with different formats) ?