Little is... (Please tell me which one is the error)

[Rosalisa]

Hi teachers,

Here is a sentence in which there is only one error among the four underlined words. Please tell me which one is the error.

Little is known about her background and early life of prison reformer Jessie donaldson Hodder.

Thanks.
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If you want to change the world, be one of the change.

[Rosalisa]

Hi teachers,

Space programs already will explored other planets - how long will it be before they explore other stars?

The underlined phrase above is a mistake but could you please tell how to correct the whole sentence?
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If you want to change the world, be one of the change.

[Mister Micawber]

.
Little is known about the background and early life of prison reformer, Jessie Donaldson Hodder.

Space programs already have explored other planets - how long will it be before they explore other stars?
.
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Native English teacher at Mister Micawber's