I need help with these last few questions. I don't know if they are correct,run-on or comma splice.

1. Mary Lou decided not to eat the alphabet soup the letters spelled out" botulism."

2.When English scientist James Smithson died in 1829, he willed his entire fortune to the United States to establsih a foundation for knowledge, that's how the Smithsonian Institution was started.

3. The word " jack-o-lantern" may have come from the legend of Irish Jack, a mean old man in life, he was condemned after death to wander the earth carrying a hollow turnip with a lump of burning coal inside.

4. people forget how large the blue whale is it has a heart as large as a Volkswagen Beetle and can hold an elephant on its tongue.

5. The famous Eiffel Tower, built for the 1889 Paris Exposition, has inspired many crazy stunts, for example, in 1891 Silvain Dornon climbed the 363 steps on stilts.

1 and 4 are run on sentences. The other three have comma splices.

http://grammar.ccc.commnet.edu/grammar/runons.htm

2. When English scientist James Smithson died in 1829, he willed his entire fortune to the United States to establish a foundation for knowledge, so that how the Smithsonian Institution was started.

3. The word " jack-o'- lantern" may have come from the legend of Irish Jack,a mean old man in life, and he was condemned after death to wander the earth carrying a hollow turnip with a lump of burning coal inside.

5.The famous Eiffel Tower, built for the 1889 Paris Exposition, has inspired many crazy stunts. For example, in 1891 Silvain Dornon climed the 363 steps on stilts.

Great!

1. This sentence is correct. There is no run-on or comma splice error.

2. This sentence is a run-on because it combines two complete sentences without proper punctuation. To fix this, you can add a period or separate the two ideas with a conjunction and a comma: "When English scientist James Smithson died in 1829, he willed his entire fortune to the United States to establish a foundation for knowledge. That's how the Smithsonian Institution was started."
3. This sentence is a run-on because it combines two complete sentences without proper punctuation. To fix this, you can add a period or separate the two ideas with a conjunction and a comma: "The word 'jack-o-lantern' may have come from the legend of Irish Jack. A mean old man in life, he was condemned after death to wander the earth carrying a hollow turnip with a lump of burning coal inside."
4. This sentence is a run-on because it combines two complete sentences without proper punctuation. To fix this, you can add a period or separate the two ideas with a conjunction and a comma: "People forget how large the blue whale is. It has a heart as large as a Volkswagen Beetle and can hold an elephant on its tongue."
5. This sentence is correct. There is no run-on or comma splice error.