A 1-cm-thick tissue sample is irradiated by an x-ray beam having a radiation flux of 6x10¹⁴ photons/(m²sec) with a radiation area of 0.06 m². The wavelength of the x-ray is 0.041 nm. The HVL of the tissue is 1.8 cm. The energy absorption coefficient of the tissue is 0.15 cm¹ for the x-ray photons. Find the total energy in keV absorbed by the tissue during 0.1-sec exposure.