L1 ELF! + (a) How are tens produced in e e' collisions? (b) If the {1+ and e beams have equal energy, what is the minimum beam energy},r required for 7' production? (e) Protons striking a stationary hydrogen target can prodnoe T's through the reaction pp r T+T'X, where X is any set of hadron(s). What is the minimum proton energy for this reaction to occur