(a) Electromagnetic wave produced in some radioactive decay is $\gamma$-rays (frequency $>$ $3 \times 10^{17} \mathrm{Hz}$ ). (b) Electromagnetic wave produced in arc welding are UV $(7.5 \times 10^{14} - 3 \times 10^{16} \mathrm{Hz}), \mathrm{IR} (3 \times 10^{12} -$ $4.3 \times 10^{14} \mathrm{Hz})$ and visible $(4.3 \times 10^{14} - 7.5 \times 10^{14}.$ $\mathrm{Hz}$ ) rays. (c) Electromagnetic wave produced in TV remote is IR rays.