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A man requires reading glasses with $+1\mathrm{.}90-D$ refractive power to read a book held $40\mathrm{.}0cm$ away with a relaxed eye. Assume the glasses are $2\mathrm{.}00cm$ from his eyes.

His uncorrected near point is $1\mathrm{.}00m.$ If one of the lenses is the one for distance vision, what should the refractive power of the other lens $($for close$-$up vision$)$ in his bifocals be to give him clear vision from $25\mathrm{.}0cm$ to infinity?