Problem $10-29$ Break$-$Even Cost $[$LO$2]$

Ught emining dode $($LEDs$)$ light bulbs have become required in secent years, but do mery mabif financial sense? Suppose a typlical $60$ wath incandevcent light bub costs $$35$ and lasts for $1\mathrm{.}000$ hours. A $15$ watl LED. which providies the same light, costs $$2\mathrm{.}90$ and What is the break$-$even cost per kilowett$-$hourt